Is zakat obligatory on money in the bank that has reached the nisab, given the existence of a rented apartment, an Islamic loan for purchasing a home, and car receivables?

There is no Zakat on a rented apartment or a car owned by a person, based on the Prophet's (peace be upon him) saying: "There is no sadaqa (Zakat) on a man concerning his slave or his horse." Zakat is due on the rent of the apartment if a full year has passed since its acquisition and it reaches the nisab. Similarly, money saved in the bank or for purchasing a house is subject to Zakat if a full lunar year has passed and it reaches the nisab. As for any debt you owe, it is deducted from the money you own, if you do not possess assets for personal use (Qunya) exceeding your needs that can be offset by the debt. The more cautious approach is not to deduct the debt and to pay Zakat on all your possessions.